Self-cleaning enclosed belt conveyor for loose materials

ABSTRACT

The self-cleaning enclosed belt conveyor for loose materials comprises a mobile belt ( 10 ) operatively connected to proper containment walls ( 2 ), where mechanical means ( 1, 15 ) are provided for, connected to said conveyor belt ( 10 ), wherein said mechanical means perform together with a bottom ( 8 ) of said containment walls ( 2 ) a recovery operation of the loose materials present in the area between the belt ( 10 ), the bottom ( 8 ) and said containment walls ( 2 ), bringing the materials back either to belt&#39;s upper stretch or to adequate containment systems.

FIELD OF INVENTION

The present invention is about a self-cleaning steel belt conveyor forloose materials.

BACKGROUND OF INVENTION

The steel belt conveyors, made of a metal net traction belt, armored bypartially overlapping plates so as to form a conveying trough, aregenerally used for the transport of materials that can be particularlyhot or aggressive due to their physical or chemical characteristics.

For example, in the disposal or treatment plants of hot ashes, producedby different combustion processes, it is necessary to move said ashescooling them for subsequent uses, avoiding their dispersion in theenvironment. In the present state of the art, in these circumstances,double mechanical conveyors are thus created, comprising a main belt forthe ashes' transport and a secondary mechanical conveyor placed belowthe main belt for collecting the materials that might fall out from thefirst one.

The primary object of the secondary mechanical conveyor is that ofavoiding the formation of material lumps that could cause someirregularities to the normal operation of the conveyor.

The previously described mechanical conveyors, even if they solve thetechnical problem illustrated above, have however some inconveniences.

The double conveyors known to the state of the art are made in acumbersome and complex fashion from a structural point of view, theirconstruction is thus more expensive than that of a single belt conveyornot only for their making but for their operation as well, furthermorebecause of their cumbersome form it is not often possible to employ themdue to the lack of sufficient space.

The double conveyor transporting system requires the use of twodifferent control units, hence greater energy consumption with respectto the use of a single conveyor.

The following patents illustrate prior art systems:

U.S. Pat. No. 5,660,283 illustrates an opened belt conveyor comprising arubber belt having several cleats integral with said rubber belt, andthus not able to rotate, having the main function of conveying thematerial.

U.S. Pat. No. 5,947,261 discloses a drag conveyor system comprisingseveral plastic paddles which provide for conveying the material in thelower section of said conveyor system only. The “self-cleaning” actionis not mechanically performed, but it is merely obtained by inclinedside walls.

U.S. Pat. No. 5,199,549 illustrates a scraper conveyor intended forconveying loose bulk material away through an opening placed at one endregion of said scraper conveyor.

The present invention's object is that of remedying the inconveniencesbelonging to the earlier state of the art.

Therefore the invention's object is a self-cleaning enclosed beltconveyer for loose materials which is reliable ad safe in its use andabove all particularly efficient in moving any kind of loose materials,even very dusty ones, without discharging any material outside.

BRIEF SUMMARY OF THE INVENTION

This invention of the self-cleaning belt conveyor for loose materialsconsists of a mobile belt operatively connected to proper containmentwalls; mechanical means are housed on the belt, which perform togetherwith the bottom of said containment walls a recovery operation of theloose materials that lay down in the area between the belt and theconveyor's bottom, bringing the materials back to said belt or towardscollection means.

In the following description the operation and the variation to theinvention's self-cleaning belts are explained, with reference to theannexed drawings wherein some preferred embodiments are shown in anexplanatory but not limiting way.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of the self-cleaning belt conveyor for loosematerials that provides for the joint work of the scraping elements (1,15) for the transport.

FIG. 2 is a vertical section of said belt conveyor which shows adifferent embodiment of the element that cleans the conveyor's lowerpart.

FIG. 3 is a side view of the self-cleaning belt conveyor that providesfor the use of both scraping elements but with a different collectionmeans other than the belt.

DESCRIPTION OF PREFERRED EMBODIMENTS

The belt conveyor has a set of containment walls comprising side walls(2), a cover (7) and a bottom (8), which enclose entirely said belt (10)except for the materials loading and unloading zones (FIG. 2).

In the area herein after referred to as back section (3) (FIG. 1) thereis a containment portion (4) fit to force the loose materials fell onthe bottom (8) to be collected or pushed forward through mechanicalmeans (1, 15) illustrated later on, or to be brought back to the beltconveyor (10) or else to be conveyed towards collection means (9) (FIG.3).

More precisely, in a first lay-out said mechanical means are connectedby hinges (5) to the conveyor belt (10) and include one or more scrapingelements (1) arranged at regular intervals. They are made of a steelplate having an end (6) with a contour fit to push and collect the loosematerials. In this way, because of the relative position where thescraping elements (1) and the bottom (8) are found when they are locatedon the lower side of the belt (10), that is along the return stretch,they are conveying and collecting all the loose materials that may bepresent on said bottom (8).

A second embodiment of the scraping elements is illustrated in FIG. 2.Said scraping elements (15) (Comprise a flexible connection elementconsisting of a section of metal net (11), or another equivalentmechanical element, connected at one end to the belt (10) and at theother end to a hanging mass (12) usually made of a steel solid piece orby another wear resistant matter, of parallelepipedal shape.

Said mass (12) has the function of keeping in tension the flexibleelement (11) during the motion of the belt (10) in the return stretchthat is when it is near the bottom (8), in order to obtain the effect ofpushing the loose material possibly collected at the bottom toward theback section (3).

In special cases, when the belts (10) must perform a long or slantedrun, the scraping elements (1, 15); assembled on the belt (10) as usual,can push what has been laid down during the return run of the belt (10)either towards the containment area (4) or towards the recoverycontainers (9). From the recovery container the material can beperiodically picked up manually or also through mechanical or pneumaticdischarge systems. In the long runs there can be more collection points,relative to the amount of loose material laid down the bottom.

In any case, regardless of the embodiment of the scraping elements (1,15), the operation of the self-cleaning belt conveyor for loosematerials occurs in the following manner.

The conveyor belt (10) is operated by an external control unit throughthe traction drum; the belt (10) is supported by upper internal rollers(16) and lower rollers (17) assembled on rest: (18) equipped withexternal bearings or bushings. At the loading zone (13) the loosematerials get loaded.

During the run on the conveyor belt, part of the material lays down onthe bottom (8) of the belt conveyor, in such case the scraping elements(1, 15) which at that moment will be on the return stretch of the belt(10), due to gravity they will have their own end near to the bottom (8)pushing and collecting the material. Close to the back section (3), ifreferring to the lay-out without the collection means (9) (FIG. 1), thescraping element (1) that is on the return side of the belt (10) willcollect the loose material held back by the tilted portion (4).

Therefore, once it is on the upper side, the scraping element (1) willunload what had been previously collected adding it to what it is comingalong the loading zone (13) and it will lean, always due to gravity, onthe belt (10) starting another cycle again.

The scraping elements (15), consisting of a section of metal net (11)and a hanging mass (12) usually made of a parallelepipedal shaped steelsolid piece are able to convey the material laid down the bottom (8) inan unloading device placed in the back section of the belt. In this casethe scraping elements (15) can be used together with the scrapingelements (1) joint working in the material transport toward theunloading devices.

It is clear from the previous description that the self-cleaning beltconveyor for loose materials according to the invention allows the useof single belts for the transport of various loose materials, reducingthe installation and operation costs, and also allowing the use of saidbelts on any kind of pattern.

Obviously, several modifications, additions, adjustments, variationsand/or substitutions could be made to the embodiments previouslydescribed in an explanatory but not limiting way, without failing out ofthe scope of protection as also recited in the following appendedclaims.

1. A self-cleaning enclosed belt conveyor for loose materials comprisinga steel conveyor belt (10) operatively connected to containment walls(2), characterized by mechanical means comprising one or more scrapingelements (1, 15), hinged upon said belt (10) and comprising a plateshaped into a contour fit to push and/or collect the loose materialspresent on the bottom, and operatively connected to said conveyor belt(10), said scraping elements (1, 15), when located on the lower side ofthe belt (10) and because of the relative position where they are found,perform together with a bottom (8) of said containment walls (2) arecovery operation of the loose materials present between the belt (10)and the bottom (8) of said containment walls (2) to bring the loosematerials back to said belt (10) or towards a collection means (9) forsaid materials, and further characterized in that said scraping element(15) is flexibly connected to said belt (10) by metal net (11) which isconnected at one end to the belt (10) and at the other end to a hangingmass (12), said hanging mass (12) keeping in tension said metal net (11)when it is near the bottom (8) in order to push the loose materialpresent at the bottom (8).
 2. A self-cleaning enclosed belt conveyor forloose materials comprising a steel conveyor belt (10) operativelyconnected to containment walls (2), characterized by mechanical meanscomprising one or more scraping elements (1, 15), hinged upon said belt(10) and comprising a plate shaped into a contour fit to push and/orcollect the loose materials present on the bottom, and operativelyconnected to said conveyor belt (10), said scraping elements (1, 15),when located on the lower side of the belt (10) and because of therelative position where they are found, perform together with a bottom(8) of said containment walls (2) a recovery operation of the loosematerials present between the belt (10) and the bottom (8) of saidcontainment walls (2) to bring the loose materials back to said belt(10) or towards a collection means (9) for said materials, and furthercharacterized in that said walls (2) comprise near a back section ofsaid belt (10) a tilted portion (4) which together with said scrapingelements (1, 15) allows the said scraping elements to hold back all thematerials collected up to that point, thus allowing disposition of thecollected materials on the bearing side of said belt (10) or in saidcollection means (9).